Links
[1] https://ifross.org/?q=artikel/freie-und-nicht-freie-lizenzen
[2] https://ifross.org/?q=user/login&destination=comment/reply/376%23comment-form
[3] mailto:carsten.schulz@ifross.de
[4] http://www.fsf.org/
[5] http://www.fsf.org/licenses/license-list.html#NonFreeSoftwareLicense
[6] https://ifross.org/?q=taxonomy/term/14
[7] https://ifross.org/?q=category/tags/fsf
[8] https://ifross.org/?q=category/tags/att-public-license